Added GHOP Student Logic.
Note that on creation of a GHOPStudent a GAE Task is created to update the taskswith the new GHOPStudent reference. This is due to the fact that we allow users to claim task without being a registered Student.
Reviewed by: Lennard de Rijk
Coverage: code coverage testing for Python
Coverage.py is a Python module that measures code coverage during test execution.
It uses the code analysis tools and tracing hooks provided in the Python standard
library to determine which lines are executable, and which have been executed.
For more information, see http://nedbatchelder.com/code/modules/coverage.html